Method and system for accessing non-volatile storage devices

• US 20070143570A1
• Filed: 12/21/2005
• Published: 06/21/2007
• Est. Priority Date: 12/21/2005
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Corporation (Western Digital Corporation)
• Inventors: Sinclair, Alan, Gorobets, Sergey
• Granted Patent: US 7,769,978 B2
• Time in Patent Office: Days
• US Class Current: 711/203
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G11C 16/10 Programming or data input circuits

Abstract

Method for transferring data between a host system and a re-programmable non-volatile mass storage system having memory cells organized into blocks of memory cells is provided. The method includes receiving data via a first interface and/or a second interface; and making data accessible via the first interface and the second interface, even if a file name is not provided by a host system or before a write operation is complete.

Claims

1. A method for transferring data between a host system and a re-programmable non-volatile mass storage system having memory cells organized into blocks of memory cells, comprising:

receiving individual files of data identified by unique file identifiers, wherein the mass storage system receives the individual files of data via a first interface and stores the received files of data indexed by the unique file identifiers;

allocating a plurality of logical block addressees to a received file data; and

updating a file allocation table (“

FAT”

) entries in the plurality of memory cells, so that the received file data can be accessible via a second interface.

2. The method of claim 1, wherein the first interface is a file interface and the second interface is a logical interface and the data is stored as files in the non-volatile memory cells.

3. The method of claim 1, wherein the mass storage system performs the allocation by maintaining an index table in the memory cells where the file data is registered and the index table is updated when the file data is written, modified and/or deleted.

4. The method of claim 1, wherein the FAT entries update and logical block address allocation is performed in real time.

5. The method of claim 1, wherein the FAT entries update and LBA allocation is performed after a write operation.

6. The method of claim 1, wherein the logical block address allocation and FAT update is performed by an embedded file system with a file output interface that is specific to a file storage back-end system.

7. The method of claim 1, wherein logical block address allocation and FAT update is performed by an embedded file system that is similar to host system'"'"'s logical block address based file system.

8. A method for transferring data between a host system and a re-programmable non-volatile mass storage system having memory cells organized into blocks of memory cells, comprising:

receiving data identified by plurality of logical addresses from the host system via a first interface, wherein the mass storage system receives the data; and

identifying the data with file identifiers, so that the data can be accessible via a second interface, even if a file name for the data is not provided by the host system.

9. The method of claim 8, wherein the data is stored as internal files with unique file names.

10. The method of claim 9, wherein the internal files with unique file names are merged into a single file after a host file name for the data is received.

11. The method of claim 9, wherein a controller assigns the unique file names.

12. The method of claim 9, wherein the unique file name is based on a logical block address for the data.

13. The method of claim 8 wherein data is stored in non-volatile memory cells as files.

14. The method of claim 8, wherein the first interface is a logical interface.

15. The method of claim 8, wherein the second interface is a file interface.

16. A method for transferring data between a host system and a re-programmable non-volatile mass storage system having memory cells organized into blocks of memory cells, comprising:

receiving data identified by a plurality of logical addresses from the host system via a first interface, wherein the mass storage system receives the data;

identifying the data with file identifiers, so that the data can be accessible via a second interface even if a file name is not provided by the host system;

storing data as internal files having unique file names; and

merging the internal files with unique file names into a single file after a host file name for the data is received.

17. The method of claim 16, wherein the data are registered with an index table that is maintained in the memory cells.

18. The method of claim 16, wherein a controller allocates the unique file names.

19. The method of claim 16, wherein the unique file names are based on a logical block address for the data.

20. The method of claim 16, wherein the data is stored in non-volatile memory cells as files.

21. The method of claim 16, wherein the first interface is a logical interface.

22. The method of claim 16, wherein the second interface is a file interface.

23. A method for transferring data between a host system and a re-programmable non-volatile mass storage system having memory cells organized into blocks of memory cells, comprising:

receiving data via a first interface and/or a second interface; and

making data accessible via the first interface and the second interface, even if a file name is not provided by a host system or before a write operation is complete.

24. The method of claim 23, wherein individual files of data identified by unique file identifiers are received by the mass storage system via the first interface and the mass storage system allocates a plurality of logical block addresses to the received file data;

and updates a file allocation table (“

FAT”

) entries in the plurality of memory cells, so that the received file data can be accessible via the second interface.

25. The method of claim 23, wherein the data is stored in a plurality of non-volatile memory cells as files.

26. The method of claim 24, wherein the FAT entries update and logical block address allocation is performed in real time or after a write operation.

27. The method of claim 24, wherein the logical block address allocation and FAT update is performed by an embedded file system with a file output interface that is specific to a file storage back-end system.

28. The method of claim 27, wherein logical block address allocation and FAT update is performed by an embedded file system that is similar to host system'"'"'s logical block address based file system.

29. The method of claim 23, wherein data received via the second interface is identified by plurality of logical addresses;

and the mass storage system identifies the data received via the second interface with file identifiers, so that the data can be accessible via the first interface.

30. The method of claim 29, wherein the data identified by plurality of logical addresses are registered with an index table that is maintained in the memory cells and stored as internal files having unique file names.

31. The method of claim 30, wherein the internal files with unique file names are merged into a single file after a host file name for the data is received.

32. The method of claim 30, wherein the index table is updated such that data identified by plurality of logical address are associated with unique file identifiers.

33. The method of claim 30, wherein the unique file names are based on a logical block address for the data.

34. The method of claim 23, wherein the first interface is a file interface.

35. The method of claim 23, wherein the second interface is a logical interface.